[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / isdn / hysdn / hysdn_proclog.c

/* $Id: hysdn_proclog.c,v 1.9.6.3 2001/09/23 22:24:54 kai Exp $
 *
 * Linux driver for HYSDN cards, /proc/net filesystem log functions.
 *
 * Author    Werner Cornelius (werner@titro.de) for Hypercope GmbH
 * Copyright 1999 by Werner Cornelius (werner@titro.de)
 *
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 *
 */

#include <linux/module.h>
#include <linux/poll.h>
#include <linux/proc_fs.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>

#include "hysdn_defs.h"

/* the proc subdir for the interface is defined in the procconf module */
extern struct proc_dir_entry *hysdn_proc_entry;

static void put_log_buffer(hysdn_card * card, char *cp);

/*************************************************/
/* structure keeping ascii log for device output */
/*************************************************/
struct log_data {
	struct log_data *next;
	unsigned long usage_cnt;/* number of files still to work */
	void *proc_ctrl;	/* pointer to own control procdata structure */
	char log_start[2];	/* log string start (final len aligned by size) */
};

/**********************************************/
/* structure holding proc entrys for one card */
/**********************************************/
struct procdata {
	struct proc_dir_entry *log;	/* log entry */
	char log_name[15];	/* log filename */
	struct log_data *log_head, *log_tail;	/* head and tail for queue */
	int if_used;		/* open count for interface */
	int volatile del_lock;	/* lock for delete operations */
	unsigned char logtmp[LOG_MAX_LINELEN];
	wait_queue_head_t rd_queue;
};


/**********************************************/
/* log function for cards error log interface */
/**********************************************/
void
hysdn_card_errlog(hysdn_card * card, tErrLogEntry * logp, int maxsize)
{
	char buf[ERRLOG_TEXT_SIZE + 40];

	sprintf(buf, "LOG 0x%08lX 0x%08lX : %s\n", logp->ulErrType, logp->ulErrSubtype, logp->ucText);
	put_log_buffer(card, buf);	/* output the string */
}				/* hysdn_card_errlog */

/***************************************************/
/* Log function using format specifiers for output */
/***************************************************/
void
hysdn_addlog(hysdn_card * card, char *fmt,...)
{
	struct procdata *pd = card->proclog;
	char *cp;
	va_list args;

	if (!pd)
		return;		/* log structure non existent */

	cp = pd->logtmp;
	cp += sprintf(cp, "HYSDN: card %d ", card->myid);

	va_start(args, fmt);
	cp += vsprintf(cp, fmt, args);
	va_end(args);
	*cp++ = '\n';
	*cp = 0;

	if (card->debug_flags & DEB_OUT_SYSLOG)
		printk(KERN_INFO "%s", pd->logtmp);
	else
		put_log_buffer(card, pd->logtmp);

}				/* hysdn_addlog */

/********************************************/
/* put an log buffer into the log queue.    */
/* This buffer will be kept until all files */
/* opened for read got the contents.        */
/* Flushes buffers not longer in use.       */
/********************************************/
static void
put_log_buffer(hysdn_card * card, char *cp)
{
	struct log_data *ib;
	struct procdata *pd = card->proclog;
	int i;
	unsigned long flags;

	if (!pd)
		return;
	if (!cp)
		return;
	if (!*cp)
		return;
	if (pd->if_used <= 0)
		return;		/* no open file for read */

	if (!(ib = kmalloc(sizeof(struct log_data) + strlen(cp), GFP_ATOMIC)))
		 return;	/* no memory */
	strcpy(ib->log_start, cp);	/* set output string */
	ib->next = NULL;
	ib->proc_ctrl = pd;	/* point to own control structure */
	spin_lock_irqsave(&card->hysdn_lock, flags);
	ib->usage_cnt = pd->if_used;
	if (!pd->log_head)
		pd->log_head = ib;	/* new head */
	else
		pd->log_tail->next = ib;	/* follows existing messages */
	pd->log_tail = ib;	/* new tail */
	i = pd->del_lock++;	/* get lock state */
	spin_unlock_irqrestore(&card->hysdn_lock, flags);

	/* delete old entrys */
	if (!i)
		while (pd->log_head->next) {
			if ((pd->log_head->usage_cnt <= 0) &&
			    (pd->log_head->next->usage_cnt <= 0)) {
				ib = pd->log_head;
				pd->log_head = pd->log_head->next;
				kfree(ib);
			} else
				break;
		}		/* pd->log_head->next */
	pd->del_lock--;		/* release lock level */
	wake_up_interruptible(&(pd->rd_queue));		/* announce new entry */
}				/* put_log_buffer */


/******************************/
/* file operations and tables */
/******************************/

/****************************************/
/* write log file -> set log level bits */
/****************************************/
static ssize_t
hysdn_log_write(struct file *file, const char __user *buf, size_t count, loff_t * off)
{
	unsigned long u = 0;
	int found = 0;
	unsigned char *cp, valbuf[128];
	long base = 10;
	hysdn_card *card = (hysdn_card *) file->private_data;

	if (count > (sizeof(valbuf) - 1))
		count = sizeof(valbuf) - 1;	/* limit length */
	if (copy_from_user(valbuf, buf, count))
		return (-EFAULT);	/* copy failed */

	valbuf[count] = 0;	/* terminating 0 */
	cp = valbuf;
	if ((count > 2) && (valbuf[0] == '0') && (valbuf[1] == 'x')) {
		cp += 2;	/* pointer after hex modifier */
		base = 16;
	}
	/* scan the input for debug flags */
	while (*cp) {
		if ((*cp >= '0') && (*cp <= '9')) {
			found = 1;
			u *= base;	/* adjust to next digit */
			u += *cp++ - '0';
			continue;
		}
		if (base != 16)
			break;	/* end of number */

		if ((*cp >= 'a') && (*cp <= 'f')) {
			found = 1;
			u *= base;	/* adjust to next digit */
			u += *cp++ - 'a' + 10;
			continue;
		}
		break;		/* terminated */
	}

	if (found) {
		card->debug_flags = u;	/* remember debug flags */
		hysdn_addlog(card, "debug set to 0x%lx", card->debug_flags);
	}
	return (count);
}				/* hysdn_log_write */

/******************/
/* read log file */
/******************/
static ssize_t
hysdn_log_read(struct file *file, char __user *buf, size_t count, loff_t * off)
{
	struct log_data *inf;
	int len;
	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	struct procdata *pd = NULL;
	hysdn_card *card;

	if (!*((struct log_data **) file->private_data)) {
		if (file->f_flags & O_NONBLOCK)
			return (-EAGAIN);

		/* sorry, but we need to search the card */
		card = card_root;
		while (card) {
			pd = card->proclog;
			if (pd->log == pde)
				break;
			card = card->next;	/* search next entry */
		}
		if (card)
			interruptible_sleep_on(&(pd->rd_queue));
		else
			return (-EAGAIN);

	}
	if (!(inf = *((struct log_data **) file->private_data)))
		return (0);

	inf->usage_cnt--;	/* new usage count */
	file->private_data = &inf->next;	/* next structure */
	if ((len = strlen(inf->log_start)) <= count) {
		if (copy_to_user(buf, inf->log_start, len))
			return -EFAULT;
		*off += len;
		return (len);
	}
	return (0);
}				/* hysdn_log_read */

/******************/
/* open log file */
/******************/
static int
hysdn_log_open(struct inode *ino, struct file *filep)
{
	hysdn_card *card;
	struct procdata *pd = NULL;
	unsigned long flags;

	lock_kernel();
	card = card_root;
	while (card) {
		pd = card->proclog;
		if (pd->log == PDE(ino))
			break;
		card = card->next;	/* search next entry */
	}
	if (!card) {
		unlock_kernel();
		return (-ENODEV);	/* device is unknown/invalid */
	}
	filep->private_data = card;	/* remember our own card */

	if ((filep->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_WRITE) {
		/* write only access -> write log level only */
	} else if ((filep->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) {

		/* read access -> log/debug read */
		spin_lock_irqsave(&card->hysdn_lock, flags);
		pd->if_used++;
		if (pd->log_head)
			filep->private_data = &pd->log_tail->next;
		else
			filep->private_data = &pd->log_head;
		spin_unlock_irqrestore(&card->hysdn_lock, flags);
	} else {		/* simultaneous read/write access forbidden ! */
		unlock_kernel();
		return (-EPERM);	/* no permission this time */
	}
	unlock_kernel();
	return nonseekable_open(ino, filep);
}				/* hysdn_log_open */

/*******************************************************************************/
/* close a cardlog file. If the file has been opened for exclusive write it is */
/* assumed as pof data input and the pof loader is noticed about.              */
/* Otherwise file is handled as log output. In this case the interface usage   */
/* count is decremented and all buffers are noticed of closing. If this file   */
/* was the last one to be closed, all buffers are freed.                       */
/*******************************************************************************/
static int
hysdn_log_close(struct inode *ino, struct file *filep)
{
	struct log_data *inf;
	struct procdata *pd;
	hysdn_card *card;
	int retval = 0;

	lock_kernel();
	if ((filep->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_WRITE) {
		/* write only access -> write debug level written */
		retval = 0;	/* success */
	} else {
		/* read access -> log/debug read, mark one further file as closed */

		pd = NULL;
		inf = *((struct log_data **) filep->private_data);	/* get first log entry */
		if (inf)
			pd = (struct procdata *) inf->proc_ctrl;	/* still entries there */
		else {
			/* no info available -> search card */
			card = card_root;
			while (card) {
				pd = card->proclog;
				if (pd->log == PDE(ino))
					break;
				card = card->next;	/* search next entry */
			}
			if (card)
				pd = card->proclog;	/* pointer to procfs log */
		}
		if (pd)
			pd->if_used--;	/* decrement interface usage count by one */

		while (inf) {
			inf->usage_cnt--;	/* decrement usage count for buffers */
			inf = inf->next;
		}

		if (pd)
			if (pd->if_used <= 0)	/* delete buffers if last file closed */
				while (pd->log_head) {
					inf = pd->log_head;
					pd->log_head = pd->log_head->next;
					kfree(inf);
				}
	}			/* read access */
	unlock_kernel();

	return (retval);
}				/* hysdn_log_close */

/*************************************************/
/* select/poll routine to be able using select() */
/*************************************************/
static unsigned int
hysdn_log_poll(struct file *file, poll_table * wait)
{
	unsigned int mask = 0;
	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	hysdn_card *card;
	struct procdata *pd = NULL;

	if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_WRITE)
		return (mask);	/* no polling for write supported */

	/* we need to search the card */
	card = card_root;
	while (card) {
		pd = card->proclog;
		if (pd->log == pde)
			break;
		card = card->next;	/* search next entry */
	}
	if (!card)
		return (mask);	/* card not found */

	poll_wait(file, &(pd->rd_queue), wait);

	if (*((struct log_data **) file->private_data))
		mask |= POLLIN | POLLRDNORM;

	return mask;
}				/* hysdn_log_poll */

/**************************************************/
/* table for log filesystem functions defined above. */
/**************************************************/
static const struct file_operations log_fops =
{
	.owner		= THIS_MODULE,
	.llseek         = no_llseek,
	.read           = hysdn_log_read,
	.write          = hysdn_log_write,
	.poll           = hysdn_log_poll,
	.open           = hysdn_log_open,
	.release        = hysdn_log_close,                                        
};


/***********************************************************************************/
/* hysdn_proclog_init is called when the module is loaded after creating the cards */
/* conf files.                                                                     */
/***********************************************************************************/
int
hysdn_proclog_init(hysdn_card * card)
{
	struct procdata *pd;

	/* create a cardlog proc entry */

	if ((pd = kzalloc(sizeof(struct procdata), GFP_KERNEL)) != NULL) {
		sprintf(pd->log_name, "%s%d", PROC_LOG_BASENAME, card->myid);
		pd->log = proc_create(pd->log_name,
				S_IFREG | S_IRUGO | S_IWUSR, hysdn_proc_entry,
				&log_fops);

		init_waitqueue_head(&(pd->rd_queue));

		card->proclog = (void *) pd;	/* remember procfs structure */
	}
	return (0);
}				/* hysdn_proclog_init */

/************************************************************************************/
/* hysdn_proclog_release is called when the module is unloaded and before the cards */
/* conf file is released                                                            */
/* The module counter is assumed to be 0 !                                          */
/************************************************************************************/
void
hysdn_proclog_release(hysdn_card * card)
{
	struct procdata *pd;

	if ((pd = (struct procdata *) card->proclog) != NULL) {
		if (pd->log)
			remove_proc_entry(pd->log_name, hysdn_proc_entry);
		kfree(pd);	/* release memory */
		card->proclog = NULL;
	}
}				/* hysdn_proclog_release */
Commit	Line	Data
1da177e4 LT	1	/* $Id: hysdn_proclog.c,v 1.9.6.3 2001/09/23 22:24:54 kai Exp $
	2	*
	3	* Linux driver for HYSDN cards, /proc/net filesystem log functions.
	4	*
	5	* Author Werner Cornelius (werner@titro.de) for Hypercope GmbH
	6	* Copyright 1999 by Werner Cornelius (werner@titro.de)
	7	*
	8	* This software may be used and distributed according to the terms
	9	* of the GNU General Public License, incorporated herein by reference.
	10	*
	11	*/
	12
	13	#include <linux/module.h>
1da177e4 LT	14	#include <linux/poll.h>
1da177e4 LT	15	#include <linux/proc_fs.h>
d43c36dc	16	#include <linux/sched.h>
5a0e3ad6	17	#include <linux/slab.h>
1da177e4 LT	18	#include <linux/smp_lock.h>
	19
	20	#include "hysdn_defs.h"
	21
	22	/* the proc subdir for the interface is defined in the procconf module */
	23	extern struct proc_dir_entry *hysdn_proc_entry;
	24
aade0e82 AB	25	static void put_log_buffer(hysdn_card * card, char *cp);
aade0e82 AB	26
1da177e4 LT	27	/*************************************************/
	28	/* structure keeping ascii log for device output */
	29	/*************************************************/
	30	struct log_data {
	31	struct log_data *next;
c721bcce	32	unsigned long usage_cnt;/* number of files still to work */
1da177e4 LT	33	void proc_ctrl; / pointer to own control procdata structure */
	34	char log_start[2]; /* log string start (final len aligned by size) */
	35	};
	36
	37	/**********************************************/
	38	/* structure holding proc entrys for one card */
	39	/**********************************************/
	40	struct procdata {
	41	struct proc_dir_entry log; / log entry */
	42	char log_name[15]; /* log filename */
	43	struct log_data log_head, log_tail; /* head and tail for queue */
	44	int if_used; /* open count for interface */
	45	int volatile del_lock; /* lock for delete operations */
c721bcce	46	unsigned char logtmp[LOG_MAX_LINELEN];
1da177e4 LT	47	wait_queue_head_t rd_queue;
	48	};
	49
	50
	51	/**********************************************/
	52	/* log function for cards error log interface */
	53	/**********************************************/
	54	void
	55	hysdn_card_errlog(hysdn_card * card, tErrLogEntry * logp, int maxsize)
	56	{
	57	char buf[ERRLOG_TEXT_SIZE + 40];
	58
	59	sprintf(buf, "LOG 0x%08lX 0x%08lX : %s\n", logp->ulErrType, logp->ulErrSubtype, logp->ucText);
	60	put_log_buffer(card, buf); /* output the string */
	61	} /* hysdn_card_errlog */
	62
	63	/***************************************************/
	64	/* Log function using format specifiers for output */
	65	/***************************************************/
	66	void
	67	hysdn_addlog(hysdn_card * card, char *fmt,...)
	68	{
	69	struct procdata *pd = card->proclog;
	70	char *cp;
	71	va_list args;
	72
	73	if (!pd)
	74	return; /* log structure non existent */
	75
	76	cp = pd->logtmp;
	77	cp += sprintf(cp, "HYSDN: card %d ", card->myid);
	78
	79	va_start(args, fmt);
	80	cp += vsprintf(cp, fmt, args);
	81	va_end(args);
	82	*cp++ = '\n';
	83	*cp = 0;
	84
	85	if (card->debug_flags & DEB_OUT_SYSLOG)
	86	printk(KERN_INFO "%s", pd->logtmp);
	87	else
	88	put_log_buffer(card, pd->logtmp);
	89
	90	} /* hysdn_addlog */
	91
	92	/********************************************/
	93	/* put an log buffer into the log queue. */
	94	/* This buffer will be kept until all files */
	95	/* opened for read got the contents. */
	96	/* Flushes buffers not longer in use. */
	97	/********************************************/
aade0e82	98	static void
1da177e4 LT	99	put_log_buffer(hysdn_card * card, char *cp)
	100	{
	101	struct log_data *ib;
	102	struct procdata *pd = card->proclog;
	103	int i;
	104	unsigned long flags;
	105
	106	if (!pd)
	107	return;
	108	if (!cp)
	109	return;
	110	if (!*cp)
	111	return;
	112	if (pd->if_used <= 0)
	113	return; /* no open file for read */
	114
5cbded58	115	if (!(ib = kmalloc(sizeof(struct log_data) + strlen(cp), GFP_ATOMIC)))
1da177e4 LT	116	return; /* no memory */
	117	strcpy(ib->log_start, cp); /* set output string */
	118	ib->next = NULL;
	119	ib->proc_ctrl = pd; /* point to own control structure */
0d9ba869	120	spin_lock_irqsave(&card->hysdn_lock, flags);
1da177e4 LT	121	ib->usage_cnt = pd->if_used;
	122	if (!pd->log_head)
	123	pd->log_head = ib; /* new head */
	124	else
	125	pd->log_tail->next = ib; /* follows existing messages */
	126	pd->log_tail = ib; /* new tail */
	127	i = pd->del_lock++; /* get lock state */
0d9ba869	128	spin_unlock_irqrestore(&card->hysdn_lock, flags);
1da177e4 LT	129
	130	/* delete old entrys */
	131	if (!i)
	132	while (pd->log_head->next) {
	133	if ((pd->log_head->usage_cnt <= 0) &&
	134	(pd->log_head->next->usage_cnt <= 0)) {
	135	ib = pd->log_head;
	136	pd->log_head = pd->log_head->next;
	137	kfree(ib);
	138	} else
	139	break;
	140	} /* pd->log_head->next */
	141	pd->del_lock--; /* release lock level */
	142	wake_up_interruptible(&(pd->rd_queue)); /* announce new entry */
	143	} /* put_log_buffer */
	144
	145
	146	/******************************/
	147	/* file operations and tables */
	148	/******************************/
	149
	150	/****************************************/
	151	/* write log file -> set log level bits */
	152	/****************************************/
	153	static ssize_t
	154	hysdn_log_write(struct file file, const char __user buf, size_t count, loff_t * off)
	155	{
c721bcce	156	unsigned long u = 0;
1da177e4	157	int found = 0;
c721bcce	158	unsigned char *cp, valbuf[128];
1da177e4 LT	159	long base = 10;
	160	hysdn_card card = (hysdn_card ) file->private_data;
	161
	162	if (count > (sizeof(valbuf) - 1))
	163	count = sizeof(valbuf) - 1; /* limit length */
	164	if (copy_from_user(valbuf, buf, count))
	165	return (-EFAULT); /* copy failed */
	166
	167	valbuf[count] = 0; /* terminating 0 */
	168	cp = valbuf;
	169	if ((count > 2) && (valbuf[0] == '0') && (valbuf[1] == 'x')) {
	170	cp += 2; /* pointer after hex modifier */
	171	base = 16;
	172	}
	173	/* scan the input for debug flags */
	174	while (*cp) {
	175	if ((cp >= '0') && (cp <= '9')) {
	176	found = 1;
	177	u = base; / adjust to next digit */
	178	u += *cp++ - '0';
	179	continue;
	180	}
	181	if (base != 16)
	182	break; /* end of number */
	183
	184	if ((cp >= 'a') && (cp <= 'f')) {
	185	found = 1;
	186	u = base; / adjust to next digit */
	187	u += *cp++ - 'a' + 10;
	188	continue;
	189	}
	190	break; /* terminated */
	191	}
	192
	193	if (found) {
	194	card->debug_flags = u; /* remember debug flags */
	195	hysdn_addlog(card, "debug set to 0x%lx", card->debug_flags);
	196	}
	197	return (count);
	198	} /* hysdn_log_write */
	199
	200	/******************/
	201	/* read log file */
	202	/******************/
	203	static ssize_t
	204	hysdn_log_read(struct file file, char __user buf, size_t count, loff_t * off)
	205	{
	206	struct log_data *inf;
	207	int len;
4482dfad	208	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
1da177e4 LT	209	struct procdata *pd = NULL;
	210	hysdn_card *card;
	211
	212	if (!((struct log_data *) file->private_data)) {
	213	if (file->f_flags & O_NONBLOCK)
	214	return (-EAGAIN);
	215
	216	/* sorry, but we need to search the card */
	217	card = card_root;
	218	while (card) {
	219	pd = card->proclog;
	220	if (pd->log == pde)
	221	break;
	222	card = card->next; /* search next entry */
	223	}
	224	if (card)
	225	interruptible_sleep_on(&(pd->rd_queue));
	226	else
	227	return (-EAGAIN);
	228
	229	}
	230	if (!(inf = ((struct log_data *) file->private_data)))
	231	return (0);
	232
	233	inf->usage_cnt--; /* new usage count */
	234	file->private_data = &inf->next; /* next structure */
	235	if ((len = strlen(inf->log_start)) <= count) {
	236	if (copy_to_user(buf, inf->log_start, len))
	237	return -EFAULT;
	238	*off += len;
	239	return (len);
	240	}
	241	return (0);
	242	} /* hysdn_log_read */
	243
	244	/******************/
	245	/* open log file */
	246	/******************/
	247	static int
	248	hysdn_log_open(struct inode ino, struct file filep)
	249	{
	250	hysdn_card *card;
	251	struct procdata *pd = NULL;
c721bcce	252	unsigned long flags;
1da177e4 LT	253
	254	lock_kernel();
	255	card = card_root;
	256	while (card) {
	257	pd = card->proclog;
	258	if (pd->log == PDE(ino))
	259	break;
	260	card = card->next; /* search next entry */
	261	}
	262	if (!card) {
	263	unlock_kernel();
	264	return (-ENODEV); /* device is unknown/invalid */
	265	}
	266	filep->private_data = card; /* remember our own card */
	267
	268	if ((filep->f_mode & (FMODE_READ \| FMODE_WRITE)) == FMODE_WRITE) {
	269	/* write only access -> write log level only */
	270	} else if ((filep->f_mode & (FMODE_READ \| FMODE_WRITE)) == FMODE_READ) {
	271
	272	/* read access -> log/debug read */
0d9ba869	273	spin_lock_irqsave(&card->hysdn_lock, flags);
1da177e4 LT	274	pd->if_used++;
	275	if (pd->log_head)
	276	filep->private_data = &pd->log_tail->next;
	277	else
	278	filep->private_data = &pd->log_head;
0d9ba869	279	spin_unlock_irqrestore(&card->hysdn_lock, flags);
1da177e4 LT	280	} else { /* simultaneous read/write access forbidden ! */
	281	unlock_kernel();
	282	return (-EPERM); /* no permission this time */
	283	}
	284	unlock_kernel();
	285	return nonseekable_open(ino, filep);
	286	} /* hysdn_log_open */
	287
	288	/*******************************************************************************/
	289	/* close a cardlog file. If the file has been opened for exclusive write it is */
	290	/* assumed as pof data input and the pof loader is noticed about. */
	291	/* Otherwise file is handled as log output. In this case the interface usage */
	292	/* count is decremented and all buffers are noticed of closing. If this file */
	293	/* was the last one to be closed, all buffers are freed. */
	294	/*******************************************************************************/
	295	static int
	296	hysdn_log_close(struct inode ino, struct file filep)
	297	{
	298	struct log_data *inf;
	299	struct procdata *pd;
	300	hysdn_card *card;
	301	int retval = 0;
1da177e4 LT	302
	303	lock_kernel();
	304	if ((filep->f_mode & (FMODE_READ \| FMODE_WRITE)) == FMODE_WRITE) {
	305	/* write only access -> write debug level written */
	306	retval = 0; /* success */
	307	} else {
	308	/* read access -> log/debug read, mark one further file as closed */
	309
	310	pd = NULL;
1da177e4 LT	311	inf = ((struct log_data ) filep->private_data); / get first log entry */
	312	if (inf)
	313	pd = (struct procdata ) inf->proc_ctrl; / still entries there */
	314	else {
	315	/* no info available -> search card */
	316	card = card_root;
	317	while (card) {
	318	pd = card->proclog;
	319	if (pd->log == PDE(ino))
	320	break;
	321	card = card->next; /* search next entry */
	322	}
	323	if (card)
	324	pd = card->proclog; /* pointer to procfs log */
	325	}
	326	if (pd)
	327	pd->if_used--; /* decrement interface usage count by one */
	328
	329	while (inf) {
	330	inf->usage_cnt--; /* decrement usage count for buffers */
	331	inf = inf->next;
	332	}
1da177e4 LT	333
	334	if (pd)
	335	if (pd->if_used <= 0) /* delete buffers if last file closed */
	336	while (pd->log_head) {
	337	inf = pd->log_head;
	338	pd->log_head = pd->log_head->next;
	339	kfree(inf);
	340	}
	341	} /* read access */
	342	unlock_kernel();
	343
	344	return (retval);
	345	} /* hysdn_log_close */
	346
	347	/*************************************************/
	348	/* select/poll routine to be able using select() */
	349	/*************************************************/
	350	static unsigned int
	351	hysdn_log_poll(struct file file, poll_table wait)
	352	{
	353	unsigned int mask = 0;
4482dfad	354	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
1da177e4 LT	355	hysdn_card *card;
	356	struct procdata *pd = NULL;
	357
	358	if ((file->f_mode & (FMODE_READ \| FMODE_WRITE)) == FMODE_WRITE)
	359	return (mask); /* no polling for write supported */
	360
	361	/* we need to search the card */
	362	card = card_root;
	363	while (card) {
	364	pd = card->proclog;
	365	if (pd->log == pde)
	366	break;
	367	card = card->next; /* search next entry */
	368	}
	369	if (!card)
	370	return (mask); /* card not found */
	371
	372	poll_wait(file, &(pd->rd_queue), wait);
	373
	374	if (((struct log_data *) file->private_data))
	375	mask \|= POLLIN \| POLLRDNORM;
	376
	377	return mask;
	378	} /* hysdn_log_poll */
	379
	380	/**************************************************/
	381	/* table for log filesystem functions defined above. */
	382	/**************************************************/
2b8693c0	383	static const struct file_operations log_fops =
1da177e4	384	{
ac41cfd1	385	.owner = THIS_MODULE,
1da177e4 LT	386	.llseek = no_llseek,
	387	.read = hysdn_log_read,
	388	.write = hysdn_log_write,
	389	.poll = hysdn_log_poll,
	390	.open = hysdn_log_open,
	391	.release = hysdn_log_close,
	392	};
	393
	394
	395	/***********************************************************************************/
	396	/* hysdn_proclog_init is called when the module is loaded after creating the cards */
	397	/* conf files. */
	398	/***********************************************************************************/
	399	int
	400	hysdn_proclog_init(hysdn_card * card)
	401	{
	402	struct procdata *pd;
	403
	404	/* create a cardlog proc entry */
	405
41f96935	406	if ((pd = kzalloc(sizeof(struct procdata), GFP_KERNEL)) != NULL) {
1da177e4	407	sprintf(pd->log_name, "%s%d", PROC_LOG_BASENAME, card->myid);
ac41cfd1 DL	408	pd->log = proc_create(pd->log_name,
	409	S_IFREG \| S_IRUGO \| S_IWUSR, hysdn_proc_entry,
	410	&log_fops);
1da177e4 LT	411
	412	init_waitqueue_head(&(pd->rd_queue));
	413
	414	card->proclog = (void ) pd; / remember procfs structure */
	415	}
	416	return (0);
	417	} /* hysdn_proclog_init */
	418
	419	/************************************************************************************/
	420	/* hysdn_proclog_release is called when the module is unloaded and before the cards */
	421	/* conf file is released */
	422	/* The module counter is assumed to be 0 ! */
	423	/************************************************************************************/
	424	void
	425	hysdn_proclog_release(hysdn_card * card)
	426	{
	427	struct procdata *pd;
	428
	429	if ((pd = (struct procdata *) card->proclog) != NULL) {
	430	if (pd->log)
	431	remove_proc_entry(pd->log_name, hysdn_proc_entry);
	432	kfree(pd); /* release memory */
	433	card->proclog = NULL;
	434	}
	435	} /* hysdn_proclog_release */